Cotton producers in southern Mali held a Climate Change Awareness Day to highlight the effects of global warming on agriculture and sustenance.

The aid agency Oxfam, which backed the event, says livelihoods in the region are threatened by unpredictable weather patterns.

Almost one third of Malians rely on the cotton industry. The crop is sometimes dubbed "white gold" because it is so important to the local economy.

But Charles Bambara of Oxfam says conditions are no longer ideal for cotton producers. He says rainfall is no longer predictable in the region.

"I think it is important because Africa is really affected by climate change effects and during this climate change day in Selingue, we listened to almost 15 farmers and cotton producers who came and gave their testimonies about how there is less and less rain in the region and the rain is not predictable anymore," Bambara said.

A survey carried out by Oxfam this year found that rainfall to Mali has dramatically decreased in the past 50 years. The rainy season once lasted for up to seven months in some cotton-producing regions; it is now over after three months.

Adequate rainfall is important to allow the cotton plants to grow and then dry out before harvesting. Bambara says this year's cotton harvest has been delayed by weeks.

"There is not even a hope for them to start the harvest in the next two or three weeks, so it is a big problem for them," he added. "The land is dry, there is no rain and they told us that in that particular region they used to have 1600 millimeters per year and now it is only 1200 millimeters per year."

According to Bambara, cotton farmers and producers noticed the unusual weather patterns long before they made the link to climate change.

"There is something happening, they don't know why but the fact is there," he said.

With nine weeks to go before December's climate change summit in Copenhagen, Oxfam says there are still plenty of questions about climate change to be raised. People in areas like the cotton belt of southern Mali are among those affected the most.